CONTENTS:
Achievetrons
Deacetylation of Telomers Crucial to Longevity in Humans
Protein Regulating Movement of Mitochondria Keeps Oxygen in Neurons from Oxygen Cutoff
Epigenetics: 100 Reasons To Change The Way We Think About Genetics
Mutations of Live Attenuated TB Vaccine Believed to Cause It to Lose Its Effectiveness
New Study Genetic Study Shows Humans and Mice Have Only Four Fifths of Common Genes Explaining Failures of Treatments Working on Mice, but Not on Humans
The Good Guide to Health
Women Better Off Choosing Unattractive Males for Mates to Increase Chances for Successful Son
Melting Ice Sheets May Threaten Northeast USA and Canada
Depleted Water Tables Induce Droughts as Experienced in Northern China and India
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Achievetrons
Lewis H. Lapham is the National Correspondent for Harper’s Magazine and the editor of Lapham’s Quarterly. http://harpers.org/archive/2009/03/0082408
Few men are so disinterested as to prefer to live in discomfort under a government which they hold to be right, rather than in comfort under one which they hold to be wrong.
Wedgwood
... The courses of undergraduate instruction at our prestigious colleges and universities no longer encourage or reward the freedoms of mind likely to disturb the country’s social and political seating plan. During the early years of the twentieth century, before America fell a foul of the dream of empire, the students on the lawns of academe, most of them inheritors of wealth and social position, already were assured of their getting ahead in the world. They could afford to take chances, to read or not to read the next day’s letter from Virginia Woolf or Julius Caesar, to mess up the protocols of political correctness, worship false gods, maybe go to Paris to try their luck with absinthe, their hand and eye at modern art or ancient decadence. If they strayed into the wilderness of politics, they did so in the manner of both Theodore and Franklin Roosevelt, with the enthusiasm of the amateur explorer. ... http://harpers.org/archive/2009/03/0082408
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(I have hope for President Obama because Columbia University requires reading the classics to understand the foibles of man, and the only one of the Ivy League schools to require such classes. Barbara Tuchman’s “The March of Folly: From Troy to Vietnam” shows that leaders, even those who head the Church, can be stupid, vain, and corrupt all at once. Since President Obama occupies the middle politically while talking left, but acting as a centrist, I have had difficulty predicting where he will fall on any particular program or policy. As you may have surmised, I don’t live in awe of the Best and the Brightest because I have seen the Clay Feet of many I have seen and experienced as a chemist in both an Academic environment and in industrial research, and my considering reading about politicians who came from the Best Schools. I love Lapham because he is from that Class, but sees the clay feet of those who run our government, financial system and unfortunately our lives. You can scroll through the various topics below and read what you might enjoy and learn. Jim)
President Barack Obama’s Christmas shopping for cabinet officers in December of last year prompted the national news media to rejoice in the glad tiding that his campaign slogan, “Change you can believe in,” was just and only that, a slogan. Instead of showing himself partial to “closet radicals” who might pose some sort of deep downfield threat to the status quo, Obama was choosing wisely from the high-end, happy few, dispensing with “the romantic and failed notion” that individuals never before seen on the White House lawn could provide the “maturity” needed “in a time of war and economic crisis.” David Brooks assured his readers in the New York Times that the incoming apparat, its members “twice as smart as the poor reporters who have to cover them,” embodied “the best of the Washington insiders.” “Achievetrons . . . who got double 800s on their SATs,” said Brooks, taking pains to list the schools from which they had received diplomas (Columbia, Harvard, Wellesley, Harvard Law, Stanford, Yale Law, Princeton, etc.) attesting to the worth of their wise counsel.
Karl Rove, former advance man for President George W. Bush, informed the Wall Street Journal that Tim Geithner (Dartmouth, Johns Hopkins) as secretary of the Treasury and Larry Summers (M.I.T., Harvard) as director of the National Economic Council were “solid picks,” both investments rated “reassuring” and “market-oriented.” ... Barack Obama’s Christmas shopping for cabinet officers in December of last year prompted the national news media to rejoice in the glad tiding that his campaign slogan, “Change you can believe in,” was just and only that, a slogan. Instead of showing himself partial to “closet radicals” who might pose some sort of deep downfield threat to the status quo, Obama was choosing wisely from the high-end, happy few, dispensing with “the romantic and failed notion” that individuals never before seen on the White House lawn could provide the “maturity” needed “in a time of war and economic crisis.” David Brooks assured his readers in the New York Times that the incoming apparat, its members “twice as smart as the poor reporters who have to cover them,” embodied “the best of the Washington insiders.” “Achievetrons . . . who got double 800s on their SATs,” said Brooks, taking pains to list the schools from which they had received diplomas (Columbia, Harvard, Wellesley, Harvard Law, Stanford, Yale Law, Princeton, etc.) attesting to the worth of their wise counsel. Karl Rove, former advance man for President George W. Bush, informed the Wall Street Journal that Tim Geithner (Dartmouth, Johns Hopkins) as secretary of the Treasury and Larry Summers (M.I.T., Harvard) as director of the National Economic Council were “solid picks,” both investments rated “reassuring” and “market-oriented.”
The mood was not as festive in the workshops of the romantic left, but even the churls who thought the appointees insufficiently progressive in their views of the American future took comfort in the remembrance of their candidate saying somewhere in a post-election speech, “Understand where the vision for change comes from. First and foremost, it comes from me.”
David Corn, the Washington bureau chief for Mother Jones, told the Washington Post that although the hotheads among his acquaintance were “disappointed, irritated or fit to be tied,” they held fast to the belief that Obama (Columbia, Harvard Law) would set the agenda, reprogram the operatives complicit in the stupidity and cynicism of the Bush and Clinton administrations; pragmatism was the watchword, and the dawning of a bright new day was guaranteed by the installation of what Brooks proclaimed a “valedictocracy,” post-partisan and non-ideological, its shoes shined, its hair combed, its ambition neatly pressed.
The recommendation deserves to be ranked with the ones until recently in vogue at the Palm Beach Country Club among the members acquainted with the achievetron Bernie Madoff. For the past sixty years the deputies assigned to engineer the domestic and foreign policies of governments newly arriving in Washington have come outfitted with similar qualifications— first-class schools, state-of-the-art networking, apprenticeship in a legislative body or a think tank—and for sixty years they have managed to weaken rather than strengthen the American democracy, ending their terms of office as objects of ridicule if not under threat of criminal arrest.
The Harvard wunderkinds (a.k.a. “the best and the brightest”) who followed President John F. Kennedy into the White House in 1961 hung around the map tables long enough to point the country in the direction of the Vietnam War. Henry Kissinger, another Harvard prodigy, imparted to American statecraft the modus operandi of a Mafia cartel. The Reagan Administration imported its book of revelation from the University of Chicago’s School of Economics (“privatization” the watchword, “unfettered free market” the Christian name for Zeus) and by so doing set in motion what lately has come to be seen as a long- running Ponzi scheme. Take into account the Ivy League’s contributions to the Bush Administration—Attorney General John Ashcroft (Yale), Secretary of Defense Donald Rumsfeld (Princeton), director of Homeland Security Michael Chertoff (Harvard)—and I can imagine a doctoral thesis commissioned by the Kennedy School of Government and meant to determine which of the country’s leading institutions of higher learning over the past fifty years has done the most damage to the health and happiness of the American people.
It’s conceivable that the Obama Administration will prove itself the exception to the rule, but when the president says that his vision for change “comes from me” he leaves open the question as to whether he intends to generate itex cathedra (Barter) or ex nihilo (Out of Nothing ) . Neither method offers much chance of success if what is wanted or required is a recasting of the American democracy on a scale comparable to Franklin Roosevelt’s New Deal. Socioeconomic alterations of a magnitude sufficient to be recognized as such tend to be collective enterprises, usually brought about by powers of mind and forces of circumstance outside, not inside, the circle of A-list opinion—the barbarians at the gates of fifth-century Rome, the sixteenth-century Protestant Reformation _personae non gratae _at the Vatican, the authors of the American Constitution far removed from the certain truths seated on velvet cushions in eighteenth-century London. Ulysses S. Grant, perhaps Lincoln’s most effective general, was virtually unknown to the War Office in Washington before the bombardment of Fort Sumter; during the Great Depression of the 1930s, FDR composed a “Brain Trust” of individuals (some of them academics, others not, none of them rounded up from the quorum of usual suspects) as willing as the president to “take a method and try it; if it fails, admit it frankly, and try another.” http://harpers.org/archive/2009/03/0082408
Deacetylation of Telomers Crucial to Longevity in Humans ... Scientists have long known that a class of proteins called sirtuins promotes fitness and longevity in most organisms ranging from single-celled yeast to mammals. At the cellular level, sirtuins protect genome integrity, enhance resistance to adverse stresses, and antagonize senescence. However, the underlying molecular mechanisms have remained poorly understood.
The team, led by senior author Shelley Berger, Ph.D., Hilary Koprowski Professor at The Wistar Institute, demonstrated for the first time a molecular target for a member of this class, Sir2, in regulation of aging in yeast cells. Sir2 removes an acetyl group attached to a specific site (lysine at position 16 or K16) on histone H4—histones are proteins that package and organize the long strands of DNA within the nucleus and also are central regulators in turning genes on and off. The study reveals that removal of this acetyl group by Sir2 near the chromosome ends—the telomeres—is important for yeast cells to maintain the ability to replicate. Researchers found that Sir2 levels decline as cells age, and there is a concomitant accumulation of the acetylation mark along with disrupted histone organization at telomeres.
Deacetylation of H4K16 by Sir2 and consequent telomere stability play a major role in maintaining long lifespan in yeast. Since sirtuins deacetylate many different proteins, these results clarify a key role of Sir2 protein in control of lifespan.
"Some modifications on histones, like this acetylation on histone H4 lysine 16, are persistent and are maintained through generations of cell divisions. This DNA-independent inheritance is called epigenetics," Berger says. "Characteristic epigenetic features have been discovered for various developmental processes in recent years. Understanding epigenetic changes associated with aging is a hugely exciting direction in aging research. It will provide insights and ideas not only for new therapies to regulate cells that have lost control of proliferation, such as 'immortal' cells found in cancers, but also for new strategies to maintain health and fitness." ... http://www.sciencedaily.com/releases/2009/06/090610133447.htm
Protein Regulating Movement of Mitochondria Keeps Oxygen in Neurons from Oxygen Cutoff
... Understanding the mechanisms that regulate the movement of mitochondria may help scientists identify how the brain's cells ward off and potentially repair damage. An example is the role that mitochondria play as a calcium buffer. One of the mitochondria's functions is to help control the concentration of calcium in the cell, which the organelles can rapidly absorb and store. This capacity is important, particularly in instances when calcium levels in the cell spike during a stroke, a condition which contributes a cascading series of events that ultimately lead to a state called excitotoxicity and cell death.
One of the keys to identifying the function of HUMMR has been the appreciation in that the body operates at a relatively low oxygen level. While the air we breath consists of approximately 20% oxygen, the cells in the brain sit at somewhere between 2-5% oxygen. This creates a "normal" state of hypoxia in the brain.
However, the concentration of oxygen in the brain can drop even further in instances such as a stroke, when blood flow to a portion of the brain is cut off. This decrease in oxygen promotes the expression of HUMMR which, in turn, mobilizes mitochondria. More mitochondria in the correct position may mean the cell has a greater capacity to filter out toxic levels of calcium. Rempe and his colleagues are now investigating the role that HUMMR may play in stroke models, particularly whether or not this activity helps protect vulnerable cells that lie just outside the core areas of the brain that are damaged by stroke. ... http://www.sciencedaily.com/releases/2009/06/090615093925.htm
Epigenetics: 100 Reasons To Change The Way We Think About Genetics
ScienceDaily (May 20, 2009) — For years, genes have been considered the one and only way biological traits could be passed down through generations of organisms.
Not anymore.
Increasingly, biologists are finding that non-genetic variation acquired during the life of an organism can sometimes be passed on to offspring—a phenomenon known as epigenetic inheritance. An article forthcoming in the July issue of The Quarterly Review of Biology lists over 100 well-documented cases of epigenetic inheritance between generations of organisms, and suggests that non-DNA inheritance happens much more often than scientists previously thought.
Biologists have suspected for years that some kind of epigenetic inheritance occurs at the cellular level. The different kinds of cells in our bodies provide an example. Skin cells and brain cells have different forms and functions, despite having exactly the same DNA. There must be mechanisms—other than DNA—that make sure skin cells stay skin cells when they divide.
Only recently, however, have researchers begun to find molecular evidence of non-DNA inheritance between organisms as well as between cells. The main question now is: How often does it happen?
"The analysis of these data shows that epigenetic inheritance is ubiquitous …," write Eva Jablonka and Gal Raz, both of Tel-Aviv University in Israel. Their article outlines inherited epigenetic variation in bacteria, protists, fungi, plants, and animals.
These findings "represent the tip of a very large iceberg," the authors say.
For example, Jablonka and Raz cite a study finding that when fruit flies are exposed to certain chemicals, at least 13 generations of their descendants are born with bristly outgrowths on their eyes. Another study found that exposing a pregnant rat to a chemical that alters reproductive hormones leads to generations of sick offspring. Yet another study shows higher rates of heart disease and diabetes in the children and grandchildren of people who were malnourished in adolescence.
In these cases, as well as the rest of the cases Jablonka and Raz cite, the source of the variation in subsequent generations was not DNA. Rather, the new traits were carried on through epigenetic means.
There are four known mechanisms for epigenetic inheritance. According to Jablonka and Raz, the best understood of these is "DNA methylation." Methyls, small chemical groups within cells, latch on to certain areas along the DNA strand. The methyls serve as a kind of switch that renders genes active or inactive.
By turning genes on and off, methyls can have a profound impact on the form and function of cells and organisms, without changing the underlying DNA. If the normal pattern of methyls is altered—by a chemical agent, for example—that new pattern can be passed to future generations.
The result, as in the case of the pregnant rats, can be dramatic and stick around for generations, despite the fact that underlying DNA remains unchanged. ... http://www.sciencedaily.com /releases/2009/05/090518111723.htm
Mutations of Live Attenuated TB Vaccine Believed to Cause It to Lose Its Effectiveness ScienceDaily (May 24, 2009) —
Not fully realized by researchers about how attenuated vaccines can mutate back to the more virulent ones as seen in the polio vaccine in India due to excretion of the modified virus into to the water supply. Viruses mutate by breaking up and recombining with fragments of other viruses. In this way they might be able to change the attenuated vaccine back to the more virulent one. So I question whether some of the weakness of vaccines could be due to the introduction of more more virulent or less effective species.
In this case the TB bacteria vaccine became less effective because it still produced antioxidants because our immune response works by an oxidation process. When the researcher first author Lakshmi Sadagopal, Ph.D., research instructor of Medicine proposed this approach, many negative responses occurred, but she was able to convince Professor Kermodle.
One good result of all the smart students going into higher income areas such as finance is that it left room for the so-called lesser students such as women and foreigners to make many of the recent breakthroughs in research such as Lakshmi Sadagopal. Bill & Melinda Gates looked into the future effects of global warming where migration of both people and bugs will bring diseases to the Developed Countries. So they have heavily funded research in Malaria and AIDs and Drug development neglected by Big Pharma to prepare us for our certain future.
Jim Kawakami
May 24, 2009
The Aeras Global TB Vaccine Foundation, supported by the Bill & Melinda Gates Foundation, has already licensed the modification technology developed by Kernodle and colleagues. Aeras is working to make the best possible modified BCG vaccine, and it has built the infrastructure to conduct clinical trials in South Africa, Kenya and India – countries with a high incidence of TB. ...
A team of Vanderbilt University Medical Center investigators has cracked one of clinical medicine's enduring mysteries – what happened to the tuberculosis vaccine. The once-effective vaccine no longer prevents the bacterial lung infection that kills more than 1.7 million people worldwide each year. ...
The current TB vaccine, known as BCG (bacille Calmette-Guérin), has been around since the 1920s. It was made by weakening (attenuating) a strain of bacteria that causes tuberculosis in cows and that genetically is 98 percent identical to the human TB germ. ...
Kernodle and colleagues came to the problem of BCG's poor activity against pulmonary TB from a different angle. They had reported in 2001 that one way TB itself evades the immune system is by producing antioxidants. Since BCG also produces antioxidants, they suggested that removing BCG's antioxidant-producing capacity might improve the vaccine.
"Our idea to take something away from BCG – and therefore theoretically attenuate it even further – was met with a lot of skepticism," Kernodle said. "But we believed our data that we could make BCG more immunogenic and safer." ...
In the current studies, first author Lakshmi Sadagopal, Ph.D., research instructor of Medicine, vaccinated mice with a modified BCG (genetically changed in three ways to reduce or eliminate the production of several antioxidants) and examined the immune response in the days following vaccination and later with a "challenge" dose of BCG.
She found that, compared to BCG, the modified BCG induced greater cytokine (immune regulatory factor) production during the early phase of the immune response, more CD8 cell-killing T cells at the peak of the primary response, and more CD4 helper T cells during the memory phase. Modified BCG also produced greater recall immune responses and was eliminated better by the vaccinated host animal than the parent BCG vaccine, which might correlate with improved safety in humans.
"At each time point of the immune response, the modified BCG vaccine worked better than the parent BCG vaccine," Kernodle said. "By targeting antioxidants that had increased in expression during decades of cultivation, we ended up making BCG more like it was back in the 1920s when it was 80 percent effective against pulmonary TB. We fixed it."
Using modern molecular techniques to reduce the activity of antioxidants below levels in naturally occurring strains, "it should be possible to make it even better than the original BCG," he added. ... http://www.sciencedaily.com/releases/2009/05/090519152446.htm
New Study Genetic Study Shows Humans and Mice Have Only Four Fifths of Common Genes Explaining Failures of Treatments Working on Mice, but Not on Humans
ScienceDaily (May 27, 2009) — A new article in PLoS Biology explores exactly what distinguishes the human genome from that of the lab mouse. In the first comprehensive comparison between the genes of mice and humans, scientists from institutions across America, Sweden and the UK reveal that there are more genetic differences between the two species than had been previously thought.
One-fifth of mouse genes are new copies that have emerged in the last 90 million years of mouse evolution. These large differences between genes in humans and the mouse are likely to reflect many of the differences that distinguish human and mouse biology.
These findings are reported in a landmark publication describing the finished genome sequence of the mouse, which, after the human, is only the second completed sequence for any mammal. That humans and mice have four-fifths of their genes in common – and that these genes have been identified - directly enhances scientists' abilities to pick out mouse genes that are most applicable to human disease. In effect, what this new research has shown is how to neatly separate biology that humans share with mice from biology found in one species only. ... http://www.sciencedaily.com /releases/2009/05/090526202722.htm
The Good Guide to Health
By CLAIRE CAIN MILLER
Published: June 14, 2009
SAN FRANCISCO — These days, every skin lotion and dish detergent on store shelves gloats about how green it is. How do shoppers know which are good for them and good for the earth?He realized he did not know what was in the lotion. He went to his office and quickly discovered that it contained a carcinogen activated by sunlight. It also contained an endocrine disruptor and two skin irritants. He also discovered that her soap included a kind of dioxane, a carcinogen, and then found that one of her brand-name toys was made with lead.
And in looking for the answer, he hatched the idea for a company that used his esoteric research on supply chain management. “All I do is study this, and I know nothing about the products I’m bringing into our house and putting in, on and around our family,” Mr. O’Rourke said. But when he wanted to find that information, he could. Most consumers would struggle to do so.
Hence GoodGuide, a Web site and iPhone application that lets consumers dig past the package’s marketing spiel by entering a product’s name and discovering its health, environmental and social impacts. ... http://www.nytimes.com/2009/06/15/technology/internet/15guide.html?em
Women Better Off Choosing Unattractive Males for Mates to Increase Chances for Successful Son
(I am unusually attracted to actress types according to Jung. Unfortunately I found them to be unsuitable marriage material. But I did notice many of the men who go into acting are Gay or of undetermined sexuality at UCLA. Anyone have a different opinion? Jim)
... In a research paper published in the Oct. 7 edition of the prestigious journal Science, UBC zoology professor Sarah Otto and graduate student Arianne Albert propose a model that explains why males in some species have extravagant displays for attracting females, while males in other species look just like females.
Many groups of animals, including humans, have an “XY” sex-determining system through which the father determines the sex of the offspring -- the offspring is female if it receives an X chromosome from the father, and vice versa. For these species, the chromosome on which flashy displays is coded will determine whether the sons or the daughters inherit the physical trait.
“If the genes coding for flashy displays are on the X, the genes from a sexy dad only appear in his daughters, making them visible to predators without improving their reproductive success, and thus favouring the evolution of preferences for dull males,” says Albert, lead author of the paper. ... http://www.sciencedaily.com/releases/2005/10/051009201943.htm
Money Worries Make Women Spend More
ScienceDaily (May 23, 2009) — At times of crisis women are more inclined to spend themselves out of misery than at stable times, a new survey suggests. Psychologists say that the recession could force more women to overspend or increase their risk of mental illness.
A survey conducted by Professor Karen Pine, from the University of Hertfordshire and author of Sheconomics, to be released on 21 May 2009 found that 79% of women said they would go on a spending spree to cheer themselves up. Professor Pine’s research concludes that some women use shopping as an emotion regulator, a way of anesthetising themselves to negative feelings or dissatisfaction with life. So worrying about money could, paradoxically, lead women to spend more.
Of the 700 women surveyed, four out of ten named ‘depression’, and six out of ten named ‘feeling a bit low’, as reasons to go on a spending spree and overspend. Women commonly expressed the view that shopping has the power to make them feel better.
Professor Pine’s research found that an intense emotional state, high or low, could send women to the shops. “This type of spending, or compensatory consumption, serves as a way of regulating intense emotions,” she said.
This ability to regulate emotions is crucial for mental and physical wellbeing and humans adopt a variety of means of doing so, including drugs and alcohol. Shopping is one method increasingly adopted by women.
“If shopping is an emotional habit for women they may feel the need to keep spending despite the economic downturn,” said Professor Pine. “Or, perhaps worse still, if they can’t spend we might see an increase in mental health problems such as anxiety and depression.” ... http://www.sciencedaily.com/releases/2009/05/090521084834.htm
Melting Ice Sheets May Threaten Northeast USA and Canada
This visualization, based on new computer modeling, shows that sea level rise may be an additional 10 centimeters (4 inches) higher by populated areas in northeastern North America than previously thought. Extreme northeastern North America and Greenland may experience even higher sea level rise. (Credit: Graphic courtesy Geophysical Research Letters, modified by UCAR)
ScienceDaily (May 28, 2009) — Melting of the Greenland ice sheet this century may drive more water than previously thought toward the already threatened coastlines of New York, Boston, Halifax, and other cities in the northeastern United States and Canada, according to new research led by the National Center for Atmospheric Research (NCAR).
The study, which is being published May 29 in Geophysical Research Letters, finds that if Greenland's ice melts at moderate to high rates, ocean circulation by 2100 may shift and cause sea levels off the northeast coast of North America to rise by about 12 to 20 inches (about 30 to 50 centimeters) more than in other coastal areas. The research builds on recent reports that have found that sea level rise associated with global warming could adversely affect North America, and its findings suggest that the situation is more threatening than previously believed.
"If the Greenland melt continues to accelerate, we could see significant impacts this century on the northeast U.S. coast from the resulting sea level rise," says NCAR scientist Aixue Hu, the lead author. "Major northeastern cities are directly in the path of the greatest rise."
A study in Nature Geoscience in March warned that warmer water temperatures could shift ocean currents in a way that would raise sea levels off the Northeast by about 8 inches (20 cm) more than the average global sea level rise. But it did not include the additional impact of Greenland's ice, which at moderate to high melt rates would further accelerate changes in ocean circulation and drive an additional 4 to 12 inches (about 10 to 30 cm) of water toward heavily populated areas of northeastern North America on top of average global sea level rise. More remote areas in extreme northeastern Canada and Greenland could see even higher sea level rise.
Scientists have been cautious about estimating average sea level rise this century in part because of complex processes within ice sheets. The 2007 assessment of the Intergovernmental Panel on Climate Change projected that sea levels worldwide could rise by an average of 7 to 23 inches (18 to 59 cm) this century, but many researchers believe the rise will be greater because of dynamic factors in ice sheets that appear to have accelerated the melting rate in recent years.
The new research was funded by the U.S. Department of Energy and by NCAR's sponsor, the National Science Foundation. It was conducted by scientists at NCAR, the University of Colorado at Boulder, and Florida State University. ... http://www.sciencedaily.com /releases/2009/05/090527121055.htm
Depleted Water Tables Induce Droughts as Experienced in Northern China and India
The Amazon Rain Forest water evaporation from trees produces its own source of heavy rains. So since we are depleting many of the water tables in Texas, Colorado, and Montana, it is likely future droughts will become more severe. Northern China went from green fields to expanding desert sands by depleting their water tables by excessive farming. The frequent dust storms in Beijing are something to dread for visitors as well as residents near these northern desert regions.
Jim Kawakami
June 4, 2009
ScienceDaily (Oct. 1, 2008) — Will there be another "dust bowl" in the Great Plains similar to the one that swept the region in the 1930s?
It depends on water storage underground. Groundwater depth has a significant effect on whether the Great Plains will have a drought or bountiful year.
Recent modeling results show that the depth of the water table, which results from lateral water flow at the surface and subsurface, determines the relative susceptibility of regions to changes in temperature and precipitation.
"Groundwater is critical to understand the processes of recharge and drought in a changing climate," said Reed Maxwell, an atmospheric scientist at Lawrence Livermore National Laboratory, who along with a colleague at Bonn University analyzed the models that appear in the Sept. 28 edition of the journal Nature Geoscience.
Maxwell and Stefan Kollet studied the response of a watershed in the southern Great Plains in Oklahoma using a groundwater/surface-water/land-surface model.
The southern Great Plains are an important agricultural region that has experienced severe droughts during the past century including the "dust bowl" of the 1930s. This area is characterized by little winter snowpack, rolling terrain and seasonal precipitation.
While the onset of droughts in the region may depend on sea surface temperature, the length and depth of major droughts appear to depend on soil moisture conditions and land-atmosphere interactions. ...
The models showed that groundwater storage acts as a moderator of watershed response and climate feedbacks. In areas with a shallow water table, changes in land conditions, such as how wet or dry the soil is and how much water is available for plant function, are related to an increase in atmospheric temperatures. In areas with deep water tables, changes at the land surface are directly related to amount of precipitation and plant type.
But in the critical zone, identified here between two and five meter's depth, there is a very strong correlation between the water table depth and the land surface.
"These findings also have strong implications for drought and show a strong dependence on areas of convergent flow and water table depth," Maxwell said. "The role of lateral subsurface flow should not be ignored in climate-change simulations and drought analysis." ... http://www.sciencedaily.com/releases/2008/09/080929133725.htm
